The 39-year-old, who led West Indies to two T20 World Cup titles, replaces Phil Simmons after he stepped down in October following their early exit from the T20 World Cup.
Andre Coley has been appointed coach of the Test side.
Coley, 48, played seven times for Jamaica and was interim West Indies coach on the Test tours of Zimbabwe and South Africa this year.
All-rounder Sammy played 38 Tests, 126 one-day internationals and 68 T20s, and since retiring in 2021 has coached in the Caribbean Premier League and Pakistan Super League.
He led West Indies to victory in the 2012 and 2016 T20 World Cups.
"It will be a challenge but one that I'm ready for and excited about," Sammy said.
"I'm really looking forward to the opportunity, especially looking at the players we have and the impact that I believe I can have in the dressing room."
Source: BBC
BDST: 1427 HRS, MAY 13, 2023
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